Adjustable gearing



April 17, 1951 A RORIVE ADJUSTABLE GEARING 'Filed Oct. 29, 1947 8 w flwm E 1 2 W/ ljm W 5 F W m 9 m 90 m INVENTOR ARlLLE RoRwE ATTORNEYSPatented Apr. 17, 1951 ADJUSTABLE GEARING Arille Rorive, Lyon, France,assignor to Societe Industrielle Generale de Mecanique Appliquee (S. I.G. M. A.), Vcnissieux (Rhone), France,

a French society Application October 29, 1947, Serial No. 782,879 InFrance November 13, 1946 The invention relates to systems including atleast one gear train with an adjustable distance between pinion axes andit is more especially, although not exclusively, concerned with systemsof this kind in which the gear train belongs to a gear pump.

The chief object of my invention is to provide a system of this kindwhich is better adapted to meet the requirements of practice than thoseused for the same purposes up to this time.

Preferred embodiments of the present invention will be hereinafterdescribed with reference to the accompanying drawing, given merely byway of examples, and in which:

Fig. 1 shows, in sectional view, a gear pump made according to myinvention;

Fig. 2 is a view of the plate that carries the pinions of the gear pumpshown by Fig. 1;

Fig. 3 shows, on a larger scale and in section on the line 33 of Fig; 1,the means for determining the adjustment of the distance between pinionaxes.

In the following description, it will be supposed that my invention isapplied to a pump intended to steady the flow of a fluid such as viscosefor feeding the spinning nozzles of an artificial'fiber spinningmachine.

Concerning the construction of the pump, with the exception of the meansfor supporting the pinionsthereof, it may be of any suitable kind, forinstance as shown by the drawing, which shows a pump constituted by aplurality of juxtaposed plates. In one of these plates, to wit plate I,located approximately in the middle part of the pump and including tworecesses, are housed the two pinions 2 and 3 which constitute the geartrain of the gear pump. One of them, the driving pinion, for instancepinion 2, is driven from the outside, while the other, the drivenpinion, in this example pinion 3, receives its movement through thedriving pinion. I provide, in said plate I on either side of the placewhere the two pinions 2 and 3 are in mesh with each other, the suctionand delivery chambers of the pump, not shown by the drawing, thesechambers communieating with the suction and delivery conduits.

I provide, on either side of said plate I, plates 4 and 5. The whole ofthese plates connected together by bolts forms the casing of the pump,which contains gear train 23.

Pinions 2 and 3 are carried by spindles or shafts 9 and II] whicharehoused in at least one of the 6 Claims. (Cl. 74397) distance between theaxes of rotation of the two" pinions.

the suction and delivery chambers, obtained by the meshing together ofthe teeth of pinions 2 and 3, depends upon the more or less perfectmanner in which the teeth of the two pinions are in mesh, therefore,among other things, upon the For practical purposes, more or lessimportan leak is unavoidable.

In the case of pumps runningat a relatively high speed, a very accuratemachining of the gears, plates, shafts and shaft housings suffices toensure a practical flow rate very close to the theoretical volumetricrate.

On the contrary, in the'case of pumps running" very slowly as it is thecase for pumps used to steady the flow rate of viscose and to feed thespinning nozzles of artificial fiber spinning machines, it is verydifiicult to obtain, in mass production, systems which, withoutadjustment after machining, give a satisfactory efliciency. Therefore itwill be necessary to provide adjust- .ment means, in particular for thedistance between axes of the pinion, which will permit of rectifying thedifferences comin from manu-.

facturing tolerances, to give the pump a satisfactory emciency.

This adjustment is preferably performed at the manufacturing works, tobe subsequently maintained, without the user of the pump being able,

even if he takes the pump to pieces for cleaning purposes, to destroythe adjustment obtained when mounting or remounting the pump.

For this purpose, the shaft or spindle of at leastone of the pinions 2and 3, preferably the driven of the shaft in question having for itseffect to adjust the distance between the axes of pinions.

2 and 3 and therefore the leak that may twKe place in the pump. l

Furthermore, and accordingto the main feature of the invention, Iprovide marking means to determine the position in which shaft It) islocated with respect to plates 4, 5, once the adjustment of the distancebetween axes is obtained.

These marking means, when the various elements of the pump areassembled, compel the fitter to give said shaft the same position thathas been given to said shaft when the pump was fitted. 'Advantageously,these marking means include on the onehand, a part hereinafter calledkey, adjustable angularly on the shaft ii] that carries the drivenpinion 3 and having a noncircular and asymmetrical shape with respect tothe axis of said shaft, and on the other hand, a

housing of a shape corresponding to that of said key and adapted to fittherewith with a play as I small as possible, this housing beingprovided in a fixed part of the'pump, 'for instance in a closure plate.

For instance, I provide on one of the ends N1 of shaft Ill a key in theform of a rectan ular plate l6 the center of which is at a distance fromthe axis of portion I and which, after assembly of the pump elements,fits in a housing I of closure plate 18, the play between the upper and,7

provide, an extension IS on the end .1 of shaft 1!] and a toothedportion rigid or integral with said extension at the end thereof, thediameter of extension 19 being smaller than the diameter both of shaftelement 10 and of toothed portion 20, whereby a groove 2.] is formedbetweenportions. H1 and 20.

Furthermore, I provide in key 16 an aperture 22 having a toothed inneredge, the teeth-of this ner. Key I6 is engaged on toothed portion 2!],

care being taken to place the key in the position that corresponds toits engagement in the housing ll of closure plate I8 and finally, afterhaving angularly positioned piece 23, as above explained, lugs 25 arefolded against key l6. Finally, closure plate i8 is fixed on the pump.Key it is thus imprisoned in its housing ll of platelS, the distancebetween the pinion axes that is determined by the angular adjustment ofspindle it remain at the desired value with a tplerance which is at mostequal to the angle corresponding to one half of a tooth of toothedsystem 22.

If the pump is to be taken in to pieces and resembled, the initialdjustment remains ensuredras long as the locking piece 23 is notseparated from key it, since the shape of key I6 and of'housing l1, sameas the asymmetrical position of the elements with respect to the axis ofshaft portion Hi or of toothed portion 20 do not permit of assemblingthe system in a position different from that chosen when the pump wasgauged.

Concerning the drive of the driving pinion 2 of a gear pump madeaccording to my invention, 7

' it ma be ensured by'securing pinion 2 directly edge correspondingexactly. to the teeth of portion 20.

I can thus engage key 16 on portion 20 in any desired annular adjustmentposition with respect to shaft l0, this adjustment position beingmaintainedby the meshing of the respective teeth of parts "5 and 20. 1

In order to lock key It on theporti'on zll'of ture 24 corresponding inshape to the aperture 22 provided in the key and'provided with fourfoldable lugs 25. In order to lock" key it, sheet 1 metal piece 23 isslipped on portion 20 until this piece is located in the spacecorresponding to g-roove'Zl that is to say beyond portion 26. Then key I6 is placed in position on portion 2i! with the desired angularadjustment, and finally piece 23 is applied against toothed portion 20with the inwardly extending teeth of piece 23 located opposite theoutwardly extending teeth of portion 2!). Lugs 25 are then folded on theouter side of key it which is thus locked in the desired angular positon with respect to shaft l0.

Adjustment of the distance between the axes of pinions 2 and 3 isobtained in the following manner; plate I and its pinions 2 and 3 areassembled with distance plates 4 and 5 (see Fig.

1), and, if necessary, with other parts of the pump, but without closureplate l8. This assembly may. be efiected through any suitable means-which serve merely to the mounting of the pumpor remain permanentlyfixed thereto. 'I'hen spindle IE3 is turned until the desired adjustmentof the distance between axes is obtained, that is to say, most often,until play between the teeth of the gears is eliminated. In thisposition, which may be indicated by a marking, I introduce locking-plate23' in the above indicated manon its shaft 9, for'instance by means of apin 26 and having shaft Qdriven through any suitable means. I

It is clearthat the distance between the axes of pinions 2v and '3 canbe adjusted in such man-i.

her as to take up as well as possible the 'func-. tional play of thepump and to ensure the best possible fi-uidtig'htness at the place-wherepinions 2 and 3 are in mesh with each other, so as thus toobtainthe-minimum leakage and the best-possible flowrate. 7

By adjusting the distance between axes and thus modifying the play, itis also possible to vary the flow rate of the pump in order to obtain amore accurate gauging of the volumetric flow rate thereof.

Adjustment of the distance betweenv axes, according to my inventionmight also be, utilized to take up the play that might be produced bywear and tear after a long time of'service.

Still another advantage of my invention consists in this; In highprecision gear pumps such as viscose pumps, the pinions must have anextremely small clearance in the recesses of the p a e n which they arehou ed. It follows hat, in known pumps, account being taken. of theposible l r n s of. manufacture. for the distance we naxes, the pinions,which are pushed away f om ch other by the pressure of the fluid forcedby the pump, been most often, not ugh their bores on their spindles,but. throu h the heads of their teeth on the, bore of the re 0.85.565provided in said plate. This constitutes a serious drawback because thegear teeth, then ctin as mil-ling tools, quickly wear off these re. ssesso that the. pumps get outof action. With? tion, are'applied by thefluid pressure against their respective spindles.

The gear train with an adjustable distance be tween axes might includeseveral driven pinions, each provided with an adjustment deviceaccording to the present invention.

In a general manner, while I have, in the above description, disclosedwhat I deem to be practical and eflicient embodiments of the presentinvention, it should be well understood that I do not wish to be limitedthereto as there might be changes made in the arrangement, dispositionand form of the parts without departing from the principle of thepresent invention as comprehended within the scope of the appendedclaims.

What I claim is:

1. In a device, a casing and two intermeshing pinions mounted in saidcasing, in combination with a crank piece including two portions ofrevolution having their axes eccentric with respect to each other, oneof said portions being housed in said casing with angular adjustmentabout its axis and the other acting as a journal for one of saidpinions, a key plate carried by the first of said cylindrical portionstransversely thereto, said key plate having a non-circular outlineeccentric with respect to the axis of said last mentioned cylindricalportion and being adjustable angularly about this axis, said casingbeing provided with an aperture having an outline of the same shape asthat of said key plate, said aperture being adapted to accommodate saidkey plate when said shaft is assembled on said casing, and means forlocking said key plate on said crank piece in a given angular positionwith respect to the axis of said first cylindrical portion thereof.

2. A device which comprises, in combination,

a plate, two intermeshing pinions mounted in said plate, a closure plateon either side of said first mentioned plate, a crank piece includingtwo portions of revolution having their axes eccentric with respect toeach other, one of said portions being housed With angular adjustmentabout its axis in one of said closure plates at right angles thereto andthe other acting as a journal for one of said pinions, a key platecarried by the first mentioned portion transversely thereto, said keyplate having a non-circular outline eccentric with respect to the axisof said last mentioned portion and being adjustable angular-1y aboutthis axis, said casing being provided with an aperture having an outlineof the same shape 5 as that of said key plate, said aperture beingadapted to accommodate said key plate when said shaft is assembled onsaid casing, and means for locking said key plate on said crank piece ina given angular position with respect to the axis of said firstmentioned portion thereof.

3. A device according to claim 2 in which the key plate is provided withan aperture having a toothed edge, the device further including a membercarried by said first mentioned portion of revolution, said memberhaving a toothed outline of the same shape as said aperture, so thatsaid key engages said member in any of a multiplicity of positions aboutthe axis of said portion.

4. A device according to claim 3 further including a plate provided withan aperture of the same shape as that of said key plate applied againstone face of said member and said key plate with its teeth out of linewith those of said key plate and said member, and means carried by saidplate and bearing on the other face of said key plate for preventingdisplacement thereof in the axial direction.

5. A device according to claim 4 in which the last mentioned meansconsist of lugs carried by said plate and adapted to be folded againstthe last mentioned face of said key plate.

6. In a device, a casing and two intermeshing pinions mounted in saidcasing, in combination with a crank piece including two portions ofrevolution having their axes eccentric with respect to each other, oneof said portions being housed in said casing with angular adjustmentabout its axis and the other acting as a journal for one of saidpinions, a key plate carried by the first of said cylindrical portionstransversely thereto, said key plate having an outline eccentric withrespect to the axis of said last mentioned cylindrical portion and beingadjustable angularly about this axis, said casing being provided with anaperture having an outline of the same shape as that of said key plate,said aperture being adapted to accommodate said key plate when saidshaft is assembled on said casing, and means for locking said key plateon said crank piece in a given angular position with respect to the axisof said first cylindrical portion thereof.

ARILLE RORIVE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 0 1,171,347 Morse Feb. 8, 19161,602,740 Bechler Oct. 12, 1926 1,712,956 Gustafson May 14, 1929 FOREIGNPATENTS 55 Number Country Date 172,159 Switzerland Sept. 30, 1934421,373 Germany Nov. 10, 1925

